Last night's exchange at the National Press Club in Canberra had a heavy emphasis on the economy and who could be trusted to best manage it.

The Prime Minister promised to introduce a bill on same-sex marriage within 100 days of being re-elected, while the Opposition Leader said he would make a decision on a second airport for Sydney in his first term of government.

Today Mr Abbott was at Melbourne's traffic management centre where he reaffirmed his commitment to provide $1.5 billion for the East West road link.

He said he wanted to be known as an "infrastructure" prime minister, if elected, and that the project would ease congestion and boost productivity

Meanwhile the Coalition has taken a swipe at Mr Rudd, claiming he cheated by using notes during last night's debate.

According to the rules "the leaders may have a pen and paper on the lectern and no other documentation or props".

KRudd can't even keep basic promise on 'no notes' for #debate as he read his opening speech closing speech and most of it in between!

Ms Milne also said voters would have benefitted from hearing the Greens' plan and from a party in Australia "that takes the science seriously and wants to see a very significant reduction in greenhouse gas emissions".

Bob Katter, leader of Katter's Australian Party, was critical of the debate because he and other minor parties were not allowed to participate.

The elephant in the room was poverty, disadvantage, compassion, kindness

Christine Milne, leader of the Greens

He has also denied rumours the party has done a preference deal with Labor saying no firm decisions have been made.

Billionaire businessman Clive Palmer said the leaders failed to talk about delivering any "real changes for our society or delivering any benefits for our citizens".

Meanwhile the Nationals Leader Warren Truss is today embarking on a tour of key seats in Queensland.

The party's prime target is Capricornia, which is currently held by retiring Labor MP Kirsten Livermore on a margin of less than 4 per cent.

Mr Truss is due to visit the electorate and promise $300,000 for Meals on Wheels in Rockhampton.

He will then head north to Proserpine, in Dawson, where Nationals MP George Christensen is fighting to hold on to his 2 per cent margin.